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1.0

Jun 28, 2018
06/18

by
Tobias Keller; Richard F. Katz

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Experimental studies of mantle petrology find that small concentrations of water and carbon dioxide have a large effect on the solidus temperature and distribution of melting in the upper mantle. However, it has remained unclear what effect small fractions of deep, volatile-rich melts have on melt transport and reactive melting in the shallow asthenosphere. Here we present theory and computations indicating that low-degree, reactive, volatile-rich melts cause channelisation of magmatic flow at...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1510.01334

0
0.0

Jun 26, 2018
06/18

by
Kristopher L. Kuhlman; Bwalya Malama; Jason E. Heath

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A multiporosity extension of classical double and triple porosity fractured rock flow models for slightly compressible fluids is presented. The multiporosity model is an adaptation of the multirate solute transport model of Haggerty and Gorelick (1995) to viscous flow in fractured rock reservoirs. It is a generalization of both pseudo-steady-state and transient interporosity flow double porosity models. The model includes a fracture continuum and an overlapping distribution of multiple rock...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1502.03067

2
2.0

Jun 26, 2018
06/18

by
Leonardo B. Monachesi; J. German Rubino; Marina Rosas-Carbajal; Damien Jougnot; Niklas Linde; Beatriz Quintal; Klaus Holliger

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The presence of mesoscopic heterogeneities in fluid-saturated porous rocks can produce measurable seismoelectric signals due to wave-induced fluid flow between regions of differing compressibility. The dependence of these signals on the petrophysical and structural characteristics of the probed rock mass remains largely unexplored. In this work, we derive an analytical solution to describe the seismoelectric response of a rock sample, containing a horizontal layer at its center, that is...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1502.07224

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3.0

Jun 27, 2018
06/18

by
H. F. Astudillo; R. Abarca-del-Rio; F. A. Borotto

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We show that the monthly recorded history (1878-2013) of the Southern Oscillation Index (SOI), a descriptor of the El Ni\~no Southern Oscillation (ENSO) phenomenon, can be well described as a dynamic system that supports an average nonlinear predictability well beyond the spring barrier. The predictability is strongly linked to a detailed knowledge of the topology of the attractor obtained by embedding the SOI index in a wavelets base state space. Using the state orbits on the attractor we show...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.04066

2
2.0

Jun 26, 2018
06/18

by
Rolf Sidler

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Phase velocities and attenuation in snow can not be explained by the widely used elastic or viscoelastic models for acoustic wave propagation. Instead, Biot's model of wave propagation in porous materials should be used. However, the application of Biot's model is complicated by the large property space of the underlying porous material. Here the properties of ice and air as well as empirical relationships are used to define the properties of snow as a function of porosity. Based on these...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1502.01284

3
3.0

Jun 27, 2018
06/18

by
Mihai Bondarescu; Ruxandra Bondarescu; Philippe Jetzer; Andrew Lundgren

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Modern optical atomic clocks along with the optical fiber technology currently being developed can measure the geoid, which is the equipotential surface that extends the mean sea level on continents, to a precision that competes with existing technology. In this proceeding, we point out that atomic clocks have the potential to not only map the sea level surface on continents, but also look at variations of the geoid as a function of time with unprecedented timing resolution. The local time...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.02853

2
2.0

Jun 28, 2018
06/18

by
Vladislav A. Yastrebov

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An elastic layer slides on a rigid flat governed by Coulomb's friction law. We demonstrate that if the coefficient of friction is high enough, the sliding localizes within stick-slip pulses, which transform into opening waves propagating at intersonic speed in the direction of sliding or, for high Poisson's ratios, at supersonic speed in the opposite direction. This sliding mode, characterized by marginal frictional dissipation, and similar to carpet fold propagation, may result in inversion of...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1507.07334

3
3.0

Jun 27, 2018
06/18

by
Ruxandra Bondarescu; Andreas Schärer; Andrew Lundgren; György Hetényi; Nicolas Houlié; Philippe Jetzer; Mihai Bondarescu

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Atomic clock technology is advancing rapidly, now reaching stabilities of $\Delta f/f \sim 10^{-18}$, which corresponds to resolving $1$ cm in equivalent geoid height over an integration timescale of about 7 hours. At this level of performance, ground-based atomic clock networks emerge as a tool for monitoring a variety of geophysical processes by directly measuring changes in the gravitational potential. Vertical changes of the clock's position due to magmatic, volcanic, post-seismic or tidal...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.02457

2
2.0

Jun 26, 2018
06/18

by
Rolf Sidler

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A method to estimate phase velocity and attenuation of acoustic waves in the presence of liquid water in a snowpack is presented. The method is based on Biot's theory of wave propagation in porous materials. Empirical relations and a priori information is used to characterize snow as a porous material as a function of porosity. Plane wave theory and an equivalent pore fluid are used to solve Biot's differential equations and to asses the impact of the air and water in the pore space. The liquid...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1502.01332

2
2.0

Jun 26, 2018
06/18

by
Dikun Yang

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This paper presents a new method of constructing physical models in a geophysical inverse problem, when there are only a few possible physical property values in the model and they are reasonably known but the geometry of the target is sought. The model consists of a fixed background and many small "particles" as building blocks that float around in the background to resemble the target by clustering. This approach contrasts the conventional geometric inversions requiring the target...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1501.06894

0
0.0

Jun 28, 2018
06/18

by
Laura Alisic; Sander Rhebergen; John F. Rudge; Richard F. Katz; Garth N. Wells

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The processes that are involved in migration and extraction of melt from the mantle are not yet fully understood. Gaining a better understanding of material properties of partially molten rock could help shed light on the behavior of melt on larger scales in the mantle. In this study, we simulate three-dimensional torsional deformation of a partially molten rock that contains a rigid, spherical inclusion. We compare the computed porosity patterns to those found in recent laboratory experiments....

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1508.03137

1
1.0

Jun 28, 2018
06/18

by
Samuel M. Weatherley; Richard F. Katz

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Recent insights to melt migration beneath ridges suggest that channelized flow is a consequence of melting of a heterogeneous mantle, and that spreading rate modulates the dynamics of the localized flow. A corollary of this finding is that both mantle het- erogeneity and spreading rate have implications for the speed and time scale of melt migration. Here, we investigate these implications using numerical models of magma flow in heterogeneous mantle beneath spreading plates. The models predict...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1509.01701

3
3.0

Jun 26, 2018
06/18

by
P. Ván; N. Mitsui; T. Hatano

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Rate- and state-dependent friction law for velocity-step and healing are analysed from a thermodynamic point of view. Assuming a logarithmic deviation from steady-state a unification of the classical Dieterich and Ruina models of rock friction is proposed.

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1501.04608

1
1.0

Jun 28, 2018
06/18

by
Hui Tang; Robert Weiss

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Modern tsunami deposits are employed to estimate the overland flow characteristics of tsunamis. With the help of the overland-flow characteristics, the characteristics of the causative tsunami wave can be estimated. The understanding of tsunami deposits has tremendously improved over the last decades. There are three prominent inversion models: Moore advection model, Soulsby's model and TsuSedMod model. TSUFLIND incorporates all three models and adds new modules to better simulate tsunami...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1507.08160

1
1.0

Jun 28, 2018
06/18

by
François Andrieu; Frédéric Schmidt; Bernard Schmitt; Sylvain Douté; Olivier Brissaud

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This article presents a set of spectro-goniometric measurements of different water ice samples and the comparison with an approximated radiative transfer model. The experiments were done using the spectro-radiogoniometer described in Brissaud et al. (2004). The radiative transfer model assumes an isotropization of the flux after the second interface and is fully described in Andrieu et al. (2015). Two kind of experiments were conducted. First, the specular spot was closely investigated, at high...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1507.04241

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5.0

Jun 26, 2018
06/18

by
Benjamin C. Bartlett; David J. Stevenson

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During the Precambrian era, Earth's decelerating rotation would have passed a 21-hour period that would have been resonant with the semidiurnal atmospheric thermal tide. Near this point, the atmospheric torque would have been maximized, being comparable in magnitude but opposite in direction to the lunar torque, halting Earth's rotational deceleration, maintaining a constant day length, as detailed by Zahnle and Walker (1987). We develop a computational model to determine necessary conditions...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1502.01421

2
2.0

Jun 27, 2018
06/18

by
Jonathan M. A. Burley; Richard F. Katz

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The geological record shows links between glacial cycles and volcanic productivity, both subaerially and at mid-ocean ridges. Sea-level-driven pressure changes could also affect chemical properties of mid-ocean ridge volcanism. We consider how changing sea-level could alter the CO2 emissions rate from mid-ocean ridges, on both the segment and global scale. We develop a simplified transport model for a highly incompatible element through a homogenous mantle; variations in the melt concentration...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1503.02308

3,749
3.7K

Jul 30, 2015
07/15

by
R Gibson

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History of the Earth podcasts Episode 372 Satellite-derived gravity

Topics: Gravity, geophysics

0
0.0

Jun 28, 2018
06/18

by
Jian-Xun Wang; Hui Tang; Heng Xiao; Robert Weiss

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Sediment deposits are the only leftover records from paleo tsunami events. Therefore, inverse modeling method based on the information contained in the deposit is an indispensable way of deciphering the quantitative characteristics of the tsunamis, e.g., the flow speed and the flow depth. While several models have been proposed to perform tsunami inversion, i.e., to infer the tsunami characteristics based on the sediment deposits, the existing methods lack mathematical rigorousness and are not...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1511.03307

0
0.0

Jun 28, 2018
06/18

by
Maya K. Buchanan; Robert E. Kopp; Michael Oppenheimer; Claudia Tebaldi

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Sea-level rise (SLR) causes estimates of flood risk made under the assumption of stationary mean sea level to be biased low. However, adjustments to flood return levels made assuming fixed increases of sea level are also inaccurate when applied to sea level that is rising over time at an uncertain rate. To accommodate both the temporal dynamics of SLR and their uncertainty, we develop an Average Annual Design Life Level (AADLL) metric and associated Design Life SLR (DL-SLR) allowances. The...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1510.08550

1
1.0

Jun 27, 2018
06/18

by
Mikael Beuthe

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Under tidal forcing, icy satellites with subsurface oceans deform as if the surface were a membrane stretched around a fluid layer. `Membrane worlds' is thus a fitting name for these bodies and membrane theory provides the perfect toolbox to predict tidal effects. I describe here a new membrane approach to tidal perturbations based on the general theory of viscoelastic-gravitational deformations of spherically symmetric bodies. The massive membrane approach leads to explicit formulas for...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1504.04574

0
0.0

Jun 28, 2018
06/18

by
T. M. Kyrke-Smith; R. F. Katz; A. C. Fowler

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Observations have long associated ice streams with the presence of meltwater at the bed. More recently, theoretical models have been able to reproduce ice-stream behaviour as a consequence of the coupled dynamics of ice and subglacial meltwater. In this paper we analyse the properties of ice streams that form in a coupled model of ice flow and subglacial hydrology. We see that there is a natural length scale defining ice stream separation and width. This arises as a result of the balance...

Topics: Physics, Geophysics

Source: http://arxiv.org/abs/1512.05181

2
2.0

Jun 28, 2018
06/18

by
A. Spanu; M. de' Michieli Vitturi; S. Barsotti

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Since the seventies, several reconstruction techniques have been proposed, and are currently used, to extrapolate and quantify eruptive parameters from sampled deposit datasets. Discrete numbers of tephra ground loadings or stratigraphic records are usually processed to estimate source eruptive values. Reconstruction techniques like Pyle, Power law and Weibull are adopted as standard to quantify the erupted mass (or volume) whereas Voronoi for reconstructing the granulometry. Reconstructed...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1509.00386

3
3.0

Jun 27, 2018
06/18

by
Liu Jiawei; Yong Wen-An

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This work is concerned with the Biot/squirt (BISQ) models for wave propagation in saturated porous media. We show that the models allow exponentially exploding solutions, as time goes to infinity, when the characteristic squirt-flow coefficient is negative or has a non-zero imaginary part. We also show that the squirt-flow coefficient does have non-zero imaginary parts for some experimental parameters. Because the models are linear, the existence of such exploding solutions indicates...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1505.02283

2
2.0

Jun 27, 2018
06/18

by
Nathanaël Schaeffer; Estelina Lora Silva; Maria Alexandra Pais

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We test the ability of large scale velocity fields inferred from geomagnetic secular variation data to produce the global magnetic field of the Earth.Our kinematic dynamo calculations use quasi-geostrophic (QG) flows inverted from geomagnetic field models which, as such, incorporate flow structures that are Earth-like and may be important for the geodynamo.Furthermore, the QG hypothesis allows straightforward prolongation of the flow from the core surface to the bulk.As expected from previous...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.02403

3
3.0

Jun 28, 2018
06/18

by
G. Hellio; N. Gillet; C. Bouligand; D. Jault

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SUMMARY We report a new method to infer continuous time series of the declination, inclination and intensity of the magnetic field from archeomagnetic data. Adopting a Bayesian perspective, we need to specify a priori knowledge about the time evolution of the magnetic field. It consists in a time correlation function that we choose to be compatible with present knowledge about the geomagnetic time spectra. The results are presented as distributions of possible values for the declination,...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.05970

1
1.0

Jun 27, 2018
06/18

by
Matteo Cerminara

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Starting from the balance equations of mass, momentum and energy we formulate an integral 1D model for a poly-disperse mixture injected in the atmosphere. We write all the equations, either in their most general formulation or in the more simplified, taking particular care in considering all the underlying hypothesis in order to make clear when it is possible and appropriate to use them. Moreover, we put all the equations in a non-dimensional form, making explicit all the dimensionless...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.01638

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6.0

Jun 27, 2018
06/18

by
August Lau; Chuan Yin

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The goal of inversion is to estimate the model which generates the data of observations with a specific modeling equation. One general approach to inversion is to use optimization methods which are algebraic in nature to define an objective function. This is the case for objective functions like minimizing RMS of amplitude, residual traveltime error in tomography, cross correlation and sometimes mixing different norms (e.g. L1 of model + L2 of RMS error). Algebraic objective function assumes...

Topics: Geophysics, Physics

Source: http://arxiv.org/abs/1506.00463

2
2.0

Jun 28, 2018
06/18

by
Behrooz Ferdowsi; Michele Griffa; Robert A. Guyer; Paul A. Johnson; Chris Marone; Jan Carmeliet

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A fundamental mystery in earthquake physics is ``how can an earthquake be triggered by distant seismic sources?'' Here, we use discrete element method simulations of a granular layer, during stick-slip, that is subject to transient vibrational excitation to gain further insight into the physics of dynamic earthquake triggering. Using Coulomb friction law for grains interaction, we observe delayed triggering of slip in the granular gouge. We find that at a critical vibrational amplitude (strain)...

Topics: Geophysics, Computational Physics, Physics

Source: http://arxiv.org/abs/1507.04710

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4.0

Jun 28, 2018
06/18

by
Monika Perkowska; Michal Wrobel; Gennady Mishuris

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A universal particle velocity based algorithm for simulating hydraulic fractures, previously proposed for Newtonian fluids, is extended to the class of shear-thinning fluids. The scheme is not limited to any particular elasticity operator or crack propagation regime. The computations are based on two dependent variables: the crack opening and the reduced particle velocity. The application of the latter facilitates utilization of the local condition of Stefan type (speed equation) to trace the...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1506.08310

3
3.0

Jun 26, 2018
06/18

by
A. Lincot; S. Merkel; Philippe Cardin

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This paper investigates whether observations of seismic anisotropy are compatible with a cubic structure of the inner core Fe alloy. We assume that anisotropy is the result of plastic deformation within a large scale flow induced by preferred growth at the inner core equator. Based on elastic moduli from the literature, bcc- or fcc-Fe produce seismic anisotropy well below seismic observations ($\textless{}0.4\%$). A Monte-Carlo approach allows us to generalize this result to any form of elastic...

Topics: Classical Physics, Physics, Geophysics

Source: http://arxiv.org/abs/1502.01270

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4.0

Jun 26, 2018
06/18

by
V. V. Flambaum; B. S. Pavlov

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It had been observed by Linkov, Petrova and Osipov (1992) that there exist periodic 4-6 hours pulses of 200 microHz seismogravitational oscillations ( SGO ) before 95 % of powerful earthquakes. We explain this by beating between an oscillation eigenmode of a whole tectonic plate and a local eigenmode of an active zone. The beating transfers the oscillation energy from the remote zone of the tectonic plate to the active zone, triggering the earthquake. Oscillation frequencies of the plate and...

Topics: Classical Physics, Physics, Geophysics

Source: http://arxiv.org/abs/1502.05485

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845

Feb 20, 2015
02/15

by
Alfred Frasheri

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Collection of publications in newspapers

Topics: geology, geophysics, Albanian renaissance

2
2.0

Jun 28, 2018
06/18

by
Yasuko Takei; Richard F. Katz

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In laboratory experiments that impose shear deformation on partially molten aggregates of initially uniform porosity, melt segregates into high-porosity sheets (bands in cross-section). The bands emerge at 15-20 degrees to the shear plane. A model of viscous anisotropy can explain these low angles whereas previous, simpler models have failed to do so. The anisotropic model is complex, however, and the reason that it produces low-angle bands has not been understood. Here we show that there are...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1506.05286

0
0.0

Jun 28, 2018
06/18

by
Ruichao Ye; Maarten de Hoop; Christopher Petrovitch; Laura Pyrak-Nolte; Lucas Wilcox

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We develop an approach for simulating acousto-elastic wave phenomena, including scattering from fluid-solid boundaries, where the solid is allowed to be anisotropic, with the Discontinuous Galerkin method. We use a coupled first-order elastic strain-velocity, acoustic velocity-pressure formulation, and append penalty terms based on interior boundary continuity conditions to the numerical (central) flux so that the consistency condition holds for the discretized Discontinuous Galerkin weak...

Topics: Geophysics, Computational Physics, Physics

Source: http://arxiv.org/abs/1511.00675

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3.0

Jun 28, 2018
06/18

by
Virginia Klausner; Esfhan A. Kherani; Marcio T. A. H. Muella; Odim Mendes; Margarete O. Domingues; Andres R. R. Papa

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The continuous geomagnetic field survey holds an important potential in future prevention of tsunami damages, and also, it could be used in tsunami forecast. In this work, we were able to detected for the first time Rayleigh and ionospheric acoustic gravity wave propagation in the Z-component of the geomagnetic field due to the Japanese tsunami, 2011 prior to the tsunami arrival. The geomagnetic measurements were obtained in the epicentral near and far-field. Also, these waves were detected...

Topics: Space Physics, Geophysics, Physics

Source: http://arxiv.org/abs/1508.00428

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2.0

Jun 27, 2018
06/18

by
Axel Modave; Amik St-Cyr; Wim A. Mulder; Tim Warburton

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Improving both accuracy and computational performance of numerical tools is a major challenge for seismic imaging and generally requires specialized implementations to make full use of modern parallel architectures. We present a computational strategy for reverse-time migration (RTM) with accelerator-aided clusters. A new imaging condition computed from the pressure and velocity fields is introduced. The model solver is based on a high-order discontinuous Galerkin time-domain (DGTD) method for...

Topics: Geophysics, Computational Physics, Physics

Source: http://arxiv.org/abs/1506.00907

0
0.0

Jun 26, 2018
06/18

by
Kambiz Razminia; Abolhassan Razminia; Delfim F. M. Torres

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We obtain an analytical solution for the pressure-transient behavior of a vertically hydraulic fractured well in a heterogeneous reservoir. The heterogeneity of the reservoir is modeled by using the concept of fractal geometry. Such reservoirs are called fractal reservoirs. According to the theory of fractional calculus, a temporal fractional derivative is applied to incorporate the memory properties of the fractal reservoir. The effect of different parameters on the computed wellbore pressure...

Topics: Physics, Geophysics, Fluid Dynamics

Source: http://arxiv.org/abs/1502.03944

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4.0

Jun 26, 2018
06/18

by
Michael A. Calkins; Keith Julien; Steven M. Tobias; Jonathan M. Aurnou

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A convection-driven multiscale dynamo model is developed in the limit of low Rossby number for the plane layer geometry in which the gravity and rotation vectors are aligned. The small-scale fluctuating dynamics are described by a magnetically-modified quasi-geostrophic equation set, and the large-scale mean dynamics are governed by a diagnostic thermal wind balance. The model utilizes three timescales that respectively characterize the convective timescale, the large-scale magnetic evolution...

Topics: Physics, Geophysics, Fluid Dynamics

Source: http://arxiv.org/abs/1502.03856

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4.0

Jun 28, 2018
06/18

by
Ilaria Spassiani; Giovanni Sebastiani

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The distribution of the magnitudes of seismic events is generally assumed to be independent on past seismicity. However, by considering events in causal relation, for example mother-daughter, it seems natural to assume that the magnitude of a daughter event is conditionally dependent on the one of the corresponding mother event. In order to find experimental evidence supporting this hypothesis, we analyze different catalogs, both real and simulated, in two different ways. From each catalog, we...

Topics: Statistics, Applications, Geophysics, Physics

Source: http://arxiv.org/abs/1508.04152

2
2.0

Jun 27, 2018
06/18

by
Jesse Taylor-West; Richard F. Katz

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Shear deformation of partially molten rock in laboratory experiments causes the emergence of melt-enriched sheets (bands in cross-section) that are aligned at about 15-20 degrees to the shear plane. Deformation and deviatoric stress also cause the coherent alignment of pores at the grain scale. This leads to a melt-preferred orientation that may, in turn, give rise to an anisotropic permeability. Here we develop a simple, general model of anisotropic permeability in partially molten rocks. We...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1505.00559

2
2.0

Jun 28, 2018
06/18

by
Robert L. Wolpert; Sarah E. Ogburn; Eliza S. Calder

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Understanding the duration of past, on-going and future volcanic eruptions is an important scientific goal and a key societal need. We present a new methodology for forecasting the duration of on-going and future lava dome eruptions based on a database (DomeHaz) recently compiled by the authors. The database includes duration and composition for 177 such eruptions, with "eruption" defined as the period encompassing individual episodes of dome growth along with associated quiescent...

Topics: Physics, Statistics, Applications, Geophysics

Source: http://arxiv.org/abs/1512.08495

3
3.0

Jun 28, 2018
06/18

by
H. Juliette T. Unwin; Garth N. Wells; Andrew W. Woods

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We investigate the long time steady-state dissolution of CO$_{2}$ in a deep saline aqquifer in the presence of a background hydrological flow. In steady-state, the distribution of CO$_2$ in the groundwater upstream of the aquifer involves a balance between three competing effects: (i) the buoyancy-driven flow of CO$_2$ saturated water; (ii) the diffusion of CO$_2$ from saturated to under-saturated water; and (iii) the advection associated with the oncoming background flow. This leads to three...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1506.04433

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Jun 28, 2018
06/18

by
Alessandro Leonardi; Falk K. Wittel; Miller Mendoza; Hans J. Herrmann

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We explore possible applications of the Lattice-Boltzmann Method for the simulation of geophysical flows. This fluid solver, while successful in other fields, is still rarely used for geotechnical applications. We show how the standard method can be modified to represent free-surface realization of mudflows, debris flows, and in general any plastic flow, through the implementation of a Bingham constitutive model. The chapter is completed by an example of a full-scale simulation of a plastic...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1509.01009

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Apr 9, 2015
04/15

by
Alfred Frasheri

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Bibliography - works in geophysics

Topics: Albania, geophysics, bibliography

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Jun 27, 2018
06/18

by
Nathanaël Machicoane; Pierre-Philippe Cortet; Bruno Voisin; Frédéric Moisy

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We analyze theoretically and experimentally the far-field viscous decay of a two-dimensional inertial wave beam emitted by a harmonic line source in a rotating fluid. By identifying the relevant conserved quantities along the wave beam, we show how the beam structure and decay exponent are governed by the multipole order of the source. Two wavemakers are considered experimentally, a pulsating and an oscillating cylinder, aiming to produce a monopole and a dipole source, respectively. The...

Topics: Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1506.02819

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Jun 28, 2018
06/18

by
Mikhail Kruglyakov; Lidia Bloshanskaya

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A new parallel solver for the volumetric integral equations (IE) of electrodynamics is presented. The solver is based on the Galerkin method which ensures the convergent numerical solution. The main features include: (i) the memory usage is 8 times lower, compared to analogous IE based algorithms, without additional restriction on the background media; (ii) accurate and stable method to compute matrix coefficients corresponding to the IE; (iii) high degree of parallelism. The solver's...

Topics: Physics, Numerical Analysis, Mathematics, Geophysics

Source: http://arxiv.org/abs/1512.06126

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Jun 28, 2018
06/18

by
Vikash Pandey; Sverre Holm

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An analogy is drawn between the diffusion-wave equations derived from the fractional Kelvin-Voigt model and those obtained from Buckingham's grain-shearing (GS) model [J. Acoust. Soc. Am. 108, 2796-2815 (2000)] of wave propagation in saturated, unconsolidated granular materials. The material impulse response function from the GS model is found to be similar to the power-law memory kernel which is inherent in the framework of fractional calculus. The compressional wave equation and shear wave...

Topics: Physics, Mathematics, Mathematical Physics, Geophysics

Source: http://arxiv.org/abs/1512.05336

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Jun 28, 2018
06/18

by
V. D. Nagornyi; S. Svitlov; A. Araya

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Iteratively Re-weighted Least Squares (IRLS) were used to simulate the $L_p$-norm approximation of the ballistic trajectory in absolute gravimeters. Two iterations of the IRLS delivered sufficient accuracy of the approximation without a significant bias. The simulations were performed on different samplings and perturbations of the trajectory. For the platykurtic distributions of the perturbations, the $L_p$-approximation with $3

Topics: Instrumentation and Detectors, Geophysics, Physics

Source: http://arxiv.org/abs/1509.00750

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Jun 28, 2018
06/18

by
Shubhangi Gupta; Rainer Helmig; Barbara Wohlmuth

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We present a hydro-geomechanical model for subsurface methane hydrate systems. Our model considers kinetic hydrate phase change and non-isothermal, multi-phase, multi-component flow in elastically deforming soils. The model accounts for the effects of hydrate phase change and pore pressure changes on the mechanical properties of the soil, and also for the effect of soil deformation on the fluid-solid interaction properties relevant to reaction and transport processes (e.g., permeability,...

Topics: Geophysics, Mathematics, Numerical Analysis, Physics

Source: http://arxiv.org/abs/1508.01421